Toilet bowl flushing water tank device

ABSTRACT

The present invention provides a toilet bowl flushing water tank device which can prevent the easy increase of a supply quantity of flushing water to a toilet bowl exceeding a predetermined quantity. The present invention provides a toilet bowl flushing water tank device which includes: a flushing water tank for storing flushing water to be supplied to a toilet bowl and forming a discharge outlet which communicates with the toilet bowl in a bottom portion thereof; a discharge valve for opening/closing the discharge outlet; a manipulation portion for performing a pull-up operation of the discharge valves a connection member for connecting the manipulation portion and the discharge valve; and a float mounted on the connection member in a state that the connection member is allowed to pass through the float and generating buoyancy for maintaining a valve-open state of the discharge valve in a state that the float is immersed in the flushing water, wherein the connection member includes an upper engaging portion and a lower engaging portion for restricting a movable range of the float on the connection member, and at least the lower engaging portion includes a lower irreversible engaging jig having physical irreversibility which prevents the removal of the lower engaging portion from the connection member unless the lower irreversible engaging jig is broken.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a toilet bowl flushing water tank device having a float generating buoyancy for maintaining a valve-open state of a discharge valve in a state that the float is immersed in flushing water.

2. Background Art

Conventionally, there has been known a toilet bowl flushing water tank device which includes a flushing water tank for storing flushing water to be supplied to a toilet bowl, a discharge outlet communicating with a flushing water supply passage which is formed in a bottom portion of the flushing water tank and communicates with the toilet bowl, a discharge valve for opening/closing the discharge outlet, a manipulation portion for performing a pull-up operation of the discharge valve, a connection member for connecting the manipulation portion and the discharge valve, and a float mounted on the connection member in a state that the connection member is allowed to pass through the float and generating buoyancy for maintaining a valve-open state of the discharge valve in a state that the float is immersed in flushing water.

Due to such a constitution, when the discharge outlet is opened by pulling up the discharge valve with the manipulation of the manipulation portion, the flushing water is supplied to the toilet bowl and hence, a waste or the like in a bowl portion of the toilet bowl can be discharged.

As this type of toilet bowl flushing water tank device, there has been known a toilet bowl flushing water tank device which can arbitrarily adjust a supply quantity of flushing water to the toilet bowl from the flushing water tank by adjusting a distance between the float and the discharge valve, wherein the distance is adjusted by changing a mounting position of the float floating which is positioned in the flushing water with a predetermined distance from the discharge valve (see JP-UM-A-62-35081 (patent document 1, for example).

SUMMARY OF THE INVENTION

However, the toilet bowl flushing water tank device described in patent document 1 allows anybody to simply change the position of the float and hence, for example, when the float is lowered and arranged at a lower position, the supply quantity of flushing water is excessively increased thus leading to the wasteful discharge of flushing water.

Accordingly, it is an object of the present invention to provide a toilet bowl flushing water tank device which can overcome the above-mentioned drawback.

(1) To achieve the above-mentioned object, according to one aspect of the present invention, there is provided a toilet bowl flushing water tank device which includes: a flushing water tank for storing flushing water to be supplied to a toilet bowl ad forming a discharge outlet which communicates with the toilet bowl in a bottom portion thereof; a discharge valve for opening/closing the discharge outlet; a manipulation portion for performing a pull-up operation of the discharge valve; a connection member for connecting the manipulation portion and the discharge valve; and a float mounted on the connection member in a state that the connection member is allowed to pass through the float and generating buoyancy for maintaining a valve-open state of the discharge valve in a state that the float is immersed in the flushing water, wherein the connection member includes an upper engaging portion and a lower engaging portion for restricting a movable range of the float on the connection member, and at least the lower engaging portion includes a lower irreversible engaging jig having physical irreversibility thus preventing the removal of the lower engaging portion from the connection member unless broken.

(2) In the toilet bowl flushing water tank device having the above-mentioned constitution (1), the upper engaging portion includes an upper irreversible engaging jig having physical irreversibility which prevents the removal of the upper engaging portion from the connection member unless broken and/or an upper reversible engaging jig having physical reversibility which allows a change of a movable range of the float due to detachable mounting of the float on the connection member.

(3) In the toilet bowl flushing water tank device having the above-mentioned constitution (2), the upper engaging portion includes the upper irreversible engaging jig and the upper reversible engaging jig, the upper irreversible engaging jig is arranged in a spaced-apart manner from the float, and the upper reversible engaging jig is mounted between the upper irreversible engaging jig and the float.

(4) In the toilet bowl flushing water tank device having any one of the above-mentioned constitutions (1) to (3), the lower engaging portion includes the lower irreversible engaging jig and a lower reversible engaging jig having physical reversibility which allows a change of a movable range of the float due to detachable mounting of the float on the connection member, the lower irreversible engaging jig is arranged in a spaced-apart manner from the float, and the lower reversible engaging jig is mounted between the lower irreversible engaging jig and the float.

(5) In the toilet bowl flushing water tank device having the above-mentioned constitution (1) or (2), a recessed portion which allows the connection member to pass therethrough is formed in a center portion of the float, and the lower irreversible engaging jig and/or the upper irreversible engaging jig is/are accommodated in the recessed portion.

(6) In the toilet bowl flushing water tank device having the above-mentioned constitution (5), only the lower irreversible engaging jig is arranged in the recessed portion, and the upper reversible engaging jig formed with a diameter larger than a diameter of the lower irreversible engaging jig is mounted in a state that the upper reversible engaging jig is brought into contact with an upper surface of the float.

According to the present invention, the connection member includes the upper engaging portion and the lower engaging portion for restricting the movable range of the float on the connection member, and at least the lower engaging portion includes the having physical irreversibility which prevents the removal of the lower engaging portion from the connection member unless the lower irreversible engaging jig is broken. Due to such a constitution, for example, a user or the like can no longer increase a supply quantity of flushing water which is properly determined corresponding to a toilet bowl by arbitrarily lowering a position of the float and hence, it is possible to prevent the wasteful discharge of flushing water in advance.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an explanatory view of a toilet bowl flushing water tank device of a first embodiment;

FIG. 2A to FIG. 2E are schematic explanatory views showing an arrangement state of a float in the toilet bowl flushing water tank device according to the first embodiment;

FIG. 3 is an explanatory view showing a modification of the arrangement state of the float in the toilet bowl flushing water tank device according to the first embodiment;

FIG. 4A to FIG. 4C are schematic explanatory views showing an arrangement state of a float in a toilet bowl flushing water tank device according to a second embodiment;

FIG. 5 is an explanatory view of a flushing water tank according to the second embodiment as viewed in a longitudinal cross section;

FIG. 6 is an explanatory view showing the mounting structure of the float which constitutes an essential part of the toilet bowl flushing water tank device according to the second embodiment as viewed in a longitudinal cross section;

FIG. 7 is a perspective view of the mounting structure of the float; and

FIG. 5A to FIG. 5E are explanatory views showing a modification of a lower irreversible engaging jig in the mounting structure of the float.

DETAIL DESCRIPTION OF THE EMBODIMENTS

Hereinafter, the present invention is explained in conjunction with drawings based on some embodiments. FIG. 1 is an explanatory view of a toilet bowl flushing water tank device, and FIG. 2A to FIG. 2E are schematic explanatory views showing an arrangement state of a float in the toilet bowl flushing water tank device. In the respective embodiments explained hereinafter, the explanation is made by giving same symbols to identical constitutional parts.

As shown in FIG. 1, a toilet bowl flushing water tank device 1 is mounted on a toilet bowl 2. The toilet bowl flushing water tank device 1 includes a flushing water tank 10 for storing flushing water 3 to be supplied to the toilet bowl 2 and forming a discharge outlet 12 which communicates with the toilet bowl 2 in a bottom portion thereof, a discharge valve 13 for opening/closing the discharge outlet 12, a manipulation portion 14 for performing a pull-up operation of the discharge valve 13, a connection member 15 for connecting the manipulation portion 14 and the discharge valve 13, and a float 16 mounted on the connection member 15 in a state that the connection member 15 is allowed to pass through the float 16 and generating buoyancy for maintaining a valve-open state of the discharge valve 13 in a state that the float 16 is immersed in the flushing water 3. Symbol 11 indicates a flushing water supply passage which communicably connects a bowl portion (not shown in the drawing) of the toile bowl 2 and the discharge outlet 12.

Further, symbol 17 indicates an overflow pipe, and the discharge valve 13 is pivotally connected to a proximal end portion of the overflow pipe 17. When the manipulation portion 14 is rotatably manipulated, the connection member 15 is pulled up interlockingly with the rotary manipulation of the manipulation portion 14, and the discharge valve 13 connected to a distal end of the connection member 15 is upwardly rotated about a pivoting portion 13 a thus releasing the discharge outlet 12 whereby the flushing water 3 is supplied into the inside of the bowl portion (not shown in the drawing) of the toilet bowl 2.

Here, the float 16 generates buoyancy in a state that the float 16 is immersed in the flushing water 3 and this buoyancy acts on the discharge valve 13 by way of the connection member 15. The buoyancy of the float 16 which acts on the discharge valve 13 is set to a value smaller than a force which the flushing water 3 applies to the discharge valve 13 based on the water pressure thereof when a water level of the flushing water 3 in the flushing water tank 10 assumes a water lever FWL, that is, when the flushing water tank 10 is fully filled with the flushing water 3. Accordingly, when the flushing water tank 10 is fully filled with the flushing water 3, the discharge valve 13 can maintain a closed state of the discharge outlet 12 even when the buoyancy of the float 16 acts on the discharge valve 13.

When the discharge valve 13 is opened so that the discharge outlet 12 is released, the flushing water 3 is supplied to the toile bowl 2. Then, when the water level of the flushing water 3 in the flushing water tank 10 is lowered and arrives at a dead water line DWL of the float 16, the buoyancy of the float 16 is cancelled or offset and hence, the discharge valve 13 is automatically closed due to a deadweight and a suction force from the discharge outlet 12 so that the supply of the flushing water 3 to the toilet bowl 2 is stopped. Accordingly, a quantity of water supplied to the toilet bowl 2 is regulated within a range from the water level FWL when the flushing water tank 10 is fully filled with the flushing water 3 to the dead water line DWL of the float 16.

First Embodiment

According to the above-mentioned constitution, as shown in FIG. 2A to FIG. 2E, in the toilet bowl flushing water tank device 1 according to the first embodiment 1, an upper engaging portion 4 and a lower engaging portion 5 for restricting a movable range of the float 16 are mounted on the connection member 15 formed of a ball chain. At least the lower engaging portion 5 includes a lower irreversible engaging jig 50 having physical irreversibility which prevents the removal of the lower engaging portion 5 from the connection member 15 unless broken.

In this embodiment, it is sufficient that the lower engaging portion 5 includes the lower irreversible engaging jig 50, and the upper engaging portion 4 may be formed of any engaging jig.

For example, the upper engaging portion 4 may be configured to include either one of an upper irreversible engaging jig 40 formed of the same member as the lower irreversible engaging jig 50 and having physical irreversibility which prevents the removal of the upper engaging portion 4 from the connection member 15 unless the upper irreversible engaging jig 40 is broken and an upper reversible engaging jig 41 having physical reversibility which allows a change of a movable range of the float 16 due to detachable mounting of the float 16 on the connection member is, or is configured to include both of the upper irreversible engaging jig 40 and the upper reversible engaging jig 41.

Here, “having physical irreversibility” implies the property that when the upper irreversible engaging jig 40 is deformed due to an external force, the deformed upper irreversible engaging jig 40 cannot restore an original state thereof. The lower irreversible engaging jig 50 is an engaging jig which cannot be removed from the connection member 15 unless the lower irreversible engaging jig 50 is broken by cutting, melting or plastic deformation, for example.

That is, in this specification, “broken” is a concept including a case that engaging member is removed from the connection member 15 by plastically deforming a material having plasticity by applying a force to the material in addition to the cutting, the melting and the like.

Accordingly, for example, the lower irreversible engaging jig 50 may be made of a material having plasticity thus allowing the removal of the from the connection member 15 by plastically deforming the lower irreversible engaging jig 50.

However, once the lower irreversible engaging jig 50 is plastically deformed and is removed from the connection member 15, even when the engaging jig may be reused as the engaging jig by deforming the engaging jig with a force to allow the removed engaging jig to restore an original state, there is no possibility that the reused engaging jig can reproduce a state completely equal to a state before the engaging jig is removed. Accordingly, it is not desirable to reuse the deformed engaging jig.

Here, although the configuration of the lower irreversible engaging jig 50 or the upper irreversible engaging jig 40 is not particularly limited, it is preferable to make the irreversible engaging jigs as light-weighted as possible while preventing the buoyancy function of the float 16 from being damaged.

On the other hand, the upper reversible engaging jig 41 is, different from the above-mentioned lower irreversible engaging jig 50 and upper irreversible engaging jig 40, an engaging member which can be easily mounted on or removed from the connection member 15 and is an engaging jig which can be used again after being removed from the connection member 15. Further, in the same manner as the lower irreversible engaging jig 50 and the upper irreversible engaging jig 40, the configuration of the upper reversible engaging jig 41 is not limited at all. Also in this case, the upper reversible engaging jig 41 is preferably as light-weighted possible due to the same reason as explained in conjunction with the lower irreversible engaging jig 50 or the upper irreversible engaging jig 40.

In this manner, due to at least the above-mentioned constitution which provides the lower irreversible engaging jig 50 to the lower engaging portion 5, the float 16 is completely prevented from moving along the connection member 15 to a position below the lower irreversible engaging jig 50.

Accordingly, the float 16 cannot be moved further downwardly unless the lower irreversible engaging jig 50 is broken. That is, the dead water line DWL of the float 16 cannot be lowered and hence, a quantity of flushing water 3 to the toilet bowl 2 cannot be changed to a value exceeding a predetermined quantity whereby there is no possibility that the flushing water 3 wastefully flows into the toilet bowl 2.

For example, assume a case in which a water-saving-type toilet bowl 2 which sets a use quantity of flushing water 3 to a value below 5 litters in one flushing operation is put on a market. Conventionally, a user or an installation provider can flush flushing water 3 of 5 litters or more into the toilet bowl 2 by suitably lowering the position of the float 16. However, according to this embodiment, with the use of the lower irreversible engaging jig 50, there is no possibility that the toilet bowl flushing water tank device is simply remodeled to enable the use of 5 litters or more of flushing water 3.

As one example of such a constitution, for example, as shown in FIG. 2A, the upper engaging portion 4 and the lower engaging portion 5 may be formed such that the upper engaging portion 4 and the lower engaging portion 5 are brought into contact with an upper surface and a lower surface of the float 16 respectively.

According to this example, a mounting position of the float 16 on the connection member 15 is fixed at one point and hence, the vertical movement of the float 16 can be prevented whereby the behavior of the float 16 in flushing water 3 becomes stable. Accordingly, when the user manipulates the manipulation portion 14, there is no possibility that the float 16 dances thus preventing a drawback that the float 16 and the connection member 15 are entangled with each other.

Further, in this example, the lower engaging portion 5 is formed of the lower irreversible engaging jig 50, while the upper engaging portion 4 is formed of the upper irreversible engaging jig 41. In this example, the lower irreversible engaging jig 50 is fixed to the connection member 15 by welding thus preventing the removable of the lower irreversible engaging jig 50 from the connection member 15 unless the lower irreversible engaging jig 50 is broken by cutting. On the other hand, a slit-shaped cut-out portion which extends radially from an insertion portion for allowing the connection member 15 to pass therethrough is formed in the upper reversible engaging jig 41 so that the upper reversible engaging jig 41 can be detachably mounted on the connection member 15 through the cut-out portion without using a tool or the like.

Accordingly, for example, as shown in FIG. 2B, the upper reversible engaging jig 41 can be removed from the connection member 15 and can change a position thereof toward an upper side.

That is, according to the example shown in FIG. 2B, although flushing water 3 which exceeds a predetermined set quantity is not allowed to flow into the toilet bowl 2, a quantity of flushing water 3 supplied to the toilet bowl 2 can be arbitrarily reset provided that a supply quantity of flushing water 3 is equal to or below the set quantity.

Further, the structure shown in FIG. 2B may be deformed into configurations shown in FIG. 2C and FIG. 2D.

These configurations are characterized in that the lower engaging portion 5 includes the lower irreversible engaging jig St, and the upper engaging portion 4 also includes the upper irreversible engaging jig 40.

In the example shown in FIG. 2C, the upper engaging portion 4 is formed of the upper irreversible engaging jig 40 and the lower engaging portion 5 is formed of the lower irreversible engaging jig 50, wherein both of the upper irreversible engaging jig 40 and the lower irreversible engaging jig 50 are formed of a member which has physical irreversibility. Further, the upper irreversible engaging jig 40 is brought into contact with an upper surface of the float 16, and the lower irreversible engaging jig 50 is brought into contact with a lower surface of the float 16.

Accordingly, in this embodiment, a mounting position of the float 16 on the connection member 15 is fixed at one point and hence, the supply quantity of flushing water 3 to the toilet bowl 2 can be fixed at a predetermined quantity. That is, the adjustment to elevate the dead water line DWL by moving the float 16 upwardly is also prohibited and hence, there is no possibility that the supply quantity of flushing water 3 to the toilet bowl 2 becomes excessively small leading to insufficient cleaning of the toilet bowl 2. Further, in the same manner as the example explained in conjunction with FIG. 2A, the float 16 is not moved vertically and hence, the behavior of the float 16 in flushing water 3 becomes stable. Accordingly, even when the manipulation portion 14 is manipulated, there is no possibility that the float 16 dances and is entangled with the connection member 15.

Also in an example shown in FIG. 2D, the upper engaging portion 4 is formed of the upper irreversible engaging jig 40, and the lower engaging portion 5 is formed of the lower irreversible engaging jig 50.

That is, as shown in FIG. 2E, a distance L between the upper irreversible engaging jig 40 and the lower irreversible engaging jig 50 is set larger than a height H of the float 16. Due to such a constitution, the float 16 is movable to some extent and, at the same time, in addition to the upper irreversible engaging jig 40, this example includes the above-mentioned upper reversible engaging jig 41 for holding the float 16 at a suitable position between the distance L.

Accordingly, in this example, the adjustment of the supply quantity of flushing water 3 to the toilet bowl 2 such that the supply quantity exceeds the predetermined supply quantity or the supply quantity is decreased to cause insufficient cleaning of the toilet bowl 2 is prohibited. That is, an upper limit and a lower limit of a range which can maintain the flushing performance are defined, and the supply quantity of flushing water 3 can be arbitrary set provided that the supply quantity falls within such a range.

In this manner, in the example shown in FIG. 2D, the upper engaging portion 4 is formed of the upper irreversible engaging jig 40 and the upper reversible engaging jig 41, the upper irreversible engaging jig 40 is arranged in a spaced apart manner from the float 16, and the upper reversible engaging jig 41 is mounted between the upper irreversible engaging jig 40 and the float 16. Due to the provision of the upper reversible engaging jig 41 in addition to the upper irreversible engaging jig 40, the user can freely set the supply quantity of flushing water 3 within the range that the cleaning performance can be maintained.

Further, as shown in FIG. 3, another example of this embodiment may be configured such that the upper engaging portion 4 is formed of the upper irreversible engaging jig 40 and the upper reversible engaging jig 41, the upper irreversible engaging jig 40 is arranged in a spaced apart manner form the float 16, and the upper reversible engaging jig 41 is mounted between the upper irreversible engaging jig 40 and the float 16, while the lower engaging portion 5 is also formed of the lower irreversible engaging jig 50 and the lower reversible engaging jig 51 having physical reversibility which allows a change of a movable range of the float 16 due to detachable mounting of the float 16 on the connection member is, the lower irreversible engaging jig 50 is arranged in a spaced apart manner from the float 16, and the lower reversible engaging jig 51 is arranged between the lower irreversible engaging jig 50 and the float 16.

Due to such a constitution, there is no possibility that the dead water line DWL of the float 16 falls out of a predetermined range (the distance L between the upper irreversible engaging jig 40 and the lower irreversible engaging jig 50) and hence, an upper limit and a lower limit of the supply quantity of flushing water 3 to the toilet bowl 2 can be defined. That is, the supply quantity of flushing water 3 to the toilet bowl 2 can be freely set by a user within a range which can maintain the cleaning performance. Further, the upper reversible engaging jig 41 and the lower reversible engaging jig 51 are mounted such that the upper reversible engaging jig 41 and the lower reversible engaging jig 51 are brought into contact with an upper surface and a lower surface of the float 16 and hence, the float 16 has almost no degree of freedom in vertical movement. Accordingly, in the same manner as the examples explained in conjunction with FIG. 2A and FIG. 2C, the behavior of the float 16 in flushing water 3 becomes stable and hence, the float 16 is set free from unstable behaviors such as dancing whereby it is possible to prevent a drawback such as the entanglement between the float 16 and the connection member 15 when the manipulation portion 14 is manipulated.

Second Embodiment

Next, a toilet bowl flushing water tank device according to a second embodiment of the present invention is explained in conjunction with FIG. 4A to FIG. 4C.

FIG. 4A to FIG. 4C are schematic explanatory views showing an arrangement state of a float in the toilet bowl flushing water tank device according to a second embodiment. In the same manner as the first embodiment explained above, a float 16 according to this embodiment is configured such that a center hole portion 16 a which constitutes a recessed portion for allowing a connection member 15 to pass therethrough is formed in a center portion of the float 16.

Here, this embodiment differs from the embodiment described above with respect to a point that a lower irreversible engaging jig 50 and/or an upper irreversible engaging jig 40 are/is accommodated or arranged in such a center hole portion 16 a.

That is, as shown in FIG. 4A to FIG. 4C, the float 16 is formed of a circular disc portion 16 d in which a through hole 16 c for allowing the connection member 15 to pass therethrough, and a float body 16 b formed of afloat-ring-shaped annular portion which is contiguously formed with a periphery of the circular disc portion 16 d. In the center hole portion 16 a formed of an inner wall of the float body 16 b where the circular disc portion 16 d is positioned, the lower irreversible engaging jig 50 and the upper irreversible engaging jig 40 with diameters smaller than a diameter of the center hole portion 16 a and larger than a diameter of a through hole 16 c are arranged.

Further, in the examples shown in FIG. 4A to FIG. 4C, even when the lower irreversible engaging jig 50 and the upper irreversible engaging jig 40 are not accommodated in the center hole portion 16 a, the lower irreversible engaging jig 50 or the upper irreversible engaging jig 40 is mounted on an upper surface or a lower surface of the float 16 in a contact state and hence, a mounting position of the float 16 on a connection member 15 is fixed at one point whereby there is no possibility that the float 16 moves vertically. Accordingly, when the manipulation portion 14 is manipulated, there is no possibility that the float 16 dances whereby a drawback that the float 16 and the connection member 15 are entangled can be prevented. Further, the jigs accommodated or arranged in the center hole portion 16 a are hardly accessible from the outside with a hand and hence, it is difficult to break either one of the upper irreversible engaging jig 40 or the lower irreversible engaging jig 50 thus making the change of the arrangement of the float 16 extremely difficult.

FIG. 4A shows an example in which both of the upper irreversible engaging jig 40 and the lower irreversible engaging jig 50 are accommodated in the center hole portion 16 a, and FIG. 4B shows an example in which only the lower irreversible engaging jig 50 is accommodated in the center hole portion 16 a. In these examples, at least the lower irreversible engaging jig 50 is accommodated in the center hole portion 16 a and hence, it is extremely difficult to change the mounting position of the float 16 from a present position to a position below the present position whereby it is impossible to increase the supply quantity of flushing water 3 to the toilet bowl 2 exceeding a predetermined quantity.

On the other hand, FIG. 4C shows an example in which only the upper irreversible engaging jig 40 is accommodated in the center hole portion 16 a. Also in this case, the lower engaging portion 5 is formed of the lower irreversible engaging jig 50 and hence, the change of the mounting position of the float 16 to a lower position is impossible unless the lower irreversible engaging jig 50 is broken. On the other hand, the upper irreversible engaging jig 40 is accommodated or arranged in the center hole portion 16 a and hence, it is extremely difficult to change the mounting position of the float 16 from a present position to a position above the present position whereby there is no possibility that the supply quantity of flushing water 3 to the toilet bowl 2 is decreased exceeding a predetermined quantity.

Here, in the respective examples shown in FIG. 4A to FIG. 4C, although the engaging jigs which are not accommodated in the center hole portion 16 a are formed of the engaging jig having physical irreversibility (the upper irreversible engaging jig 40 or the lower irreversible engaging jig 50), the jigs which are not accommodated in the center hole portion 16 a may be formed of a jig having reversibility with respect to the engaging jig.

As an example of such an embodiment, only the lower irreversible engaging jig so is arranged in the center hole portion 16 a, and the upper reversible engaging jig 41 formed with a diameter larger than a diameter of the lower irreversible engaging jig 50 is mounted in a state that the upper reversible engaging jig 41 is brought into contact with an upper surface of the float 16. This example is more specifically explained in conjunction with FIG. 5 to FIG. 7.

FIG. 5 is an explanatory view of a flushing water tank 10 of the toilet bowl flushing water tank device 1 as viewed in a longitudinal cross section. FIG. 6 is an explanatory view showing the mounting structure of the float 16 which constitutes an essential part of the toilet bowl flushing water tank device 1 as viewed in a longitudinal cross section. FIG. 7 is a perspective view of the mounting structure of the float 16. Here, the flushing water tank 10 and the float 16 of this embodiment basically have the same constitution as the flushing water tank 10 and the float 16 explained in conjunction with FIG. 1 and hence, constitutional elements identical with the constitutional elements explained in conjunction with FIG. 1 are given same symbols.

The flushing water tank 10 shown in FIG. 5 is formed in a box shape and has an upper opening thereof covered with a lid body 10 b. Here, a supply quantity of flushing water 3 to the toilet bowl 2 (see FIG. 1) is set to 5 litters.

Further, the flushing water tank 10 includes a water feed device 6 for supplying water into the inside of a tank body, and a water supply device 7 for supplying water reserved in the inside of the flushing water tank 10 to the toilet bowl 2 by discharging water toward the toilet bowl 2. The flushing water tank 10 reserves water supplied from a water feed source (not shown in the drawing) by the water feed device 6 and, at the same time, supplies 5 litters of reserved water to the toilet bowl 2 as flushing water by the water supply device 7.

The water feed device 6 includes a water feed pipe 60 arranged upright on a left side in the flushing water tank 10 and having a lower end thereof connected to the water feed source, a water feed valve 61 mounted on an upper end of the water feed pipe 60 for changing over pouring of flushing water into the flushing water tank 10 and stopping of such pouring, and a float portion 62 provided for performing a changeover operation of the water feed valve 61 between pouring and stopping of water due to the vertical movement of the float portion 62 in response to the fluctuation of water level in the flushing water tank 10.

The water supply device 7 includes a discharge valve 13 for opening/closing a discharge outlet 12, a manipulation portion 14 for opening/closing the discharge outlet 12 by pulling up the discharge valve 13 by an external operation, a connection member 15 for connecting the manipulation portion 14 and the discharge valve 13, and a float 16 mounted on the connection member 15 in a state that the connection member 15 is allowed to pass through the float 16 and generating buoyancy for maintaining a valve-open state of the discharge valve 13 in a state that the float 16 is immersed in the flushing water 3 (see FIG. 1).

One end of a rotational shaft 71 is connected to a manipulation lever 14 a which constitutes the manipulation portion 14 and another end of the rotational shaft 71 extends substantially horizontally in the flushing water tank 10. That is, the rotational shaft 71 is configured to be rotatable by the manipulation of the manipulation lever 14 a and, at the same time, the connection member is which is constituted of a chain body formed by connecting a plurality of ring members 15 a extends downwardly from another end of the rotational shaft 71. Due to such a constitution, when a user manipulates the manipulation lever 14 a, the discharge valve 13 connected to a lower end of the connection member 15 is pulled up so that the discharge outlet 12 is opened.

In this example, the chain body which constitutes the connection member 15 is formed by connecting a plurality of string-like ring members 15 a different from the chain body constituted of the ball chain. However, the connection member 15 is not limited to such a chain body, and the connection member may be formed of a strip chain. Further, a material of the connection member is not particularly limited. The connection member 15 may preferably be made of a light-weighted sufficiently waterproof material.

Here, in FIG. 5, symbol 12 a indicates a discharge guide sleeve. The discharge guide sleeve 12 a is fitted in an inner peripheral surface of the discharge outlet 12 formed in a center portion of a bottom portion 10 a of the flushing water tank 10. The discharge guide sleeve 12 a has an upper end thereof projected toward the inside of the flushing water tank 10 and a lower end thereof projected toward the inside of the flushing water tank 10. Due to such a constitution, the discharge guide tube 12 a guides discharging of flushing water 3 into the toilet bowl 2. Further, an upper end surface of the discharge guide tube 12 a performs a function of a valve seat which receives an open/close operation of the discharge valve 13.

In the above-mentioned constitution, as explained in conjunction with FIG. 1 previously, the float 16 is mounted above the discharge valve 13 with a predetermined distance held therebetween.

Further, in the mounting structure of the float 16 to the connection member 15, an shown in FIG. 6 and FIG. 7, only the lower irreversible engaging jig 50 is arranged in the center hole portion 16 a, and the upper reversible engaging jig 41 formed with a diameter larger than a diameter of the lower irreversible engaging jig 50 is mounted in a state that the upper reversible engaging jig 41 is brought into contact with an upper surface of the float 16.

Here, the specific constitution of the lower irreversible engaging jig 50 and the upper reversible engaging jig 41 of this embodiment is explained.

First of all, to explain the lower irreversible engaging jig 50 accommodated or arranged in the center hole portion 16 a formed in the float 16, the lower irreversible engaging jig 50 is, as shown in FIG. 6 and FIG. 7, formed by making use of a binding band (so-called “INSULOK”™ which cannot be loosened unless broken by cutting once the binding band is bound.

That is, a distal end of a bank portion 50 a of the binding band having a predetermined length is made to pass through the ring member 15 a of the connection member 15, is inserted into a locking portion 50 b, the band portion 50 a is sufficiently fastened by pulling and, thereafter, a portion of the band portion 50 a projecting from the locking portion 50 b is cut off.

With the use of such a binding band, it is possible to extremely easily form the lower irreversible engaging jig 50. Here, to make use of such a binding band, a width of the ring member 15 a of the chain body constituting the connection member 15 is set corresponding to an insertion hole 16 c formed in a circular disc portion 16 d of the float 16. That is, the width of the ring member 15 a is set to a value which allows the smooth insertion of the ring member 15 a into the insertion hole 16 c through the insertion hole 16 c and never fails to prevent the removal of the lower irreversible engaging jig 50 from the insertion hole 16 c when the lower irreversible engaging jig 50 is mounted on the connection member 15.

On the other hand, as shown in FIG. 6 and FIG. 7, it is sufficient for the upper reversible engaging jig 41 mounted on the float 16 to be brought into contact with an upper surface of the float 16 to have a function of an engaging member which prevents the upward movement of the float 16 along the connection member 15. Accordingly, a slit-shaped cutoff portion 41 b is formed in a disc-shaped engaging jig body 41 a such that the cutoff portion 41 b extends toward the center from a portion of a periphery of the engaging jig body 41 a, and the ring member 15 a of the connection member 15 can be removed from or inserted into the center portion of the engaging body 41 a through the cutoff portion 41 b. Symbol 41 c indicates an engaging portion having an approximately U-shape in transverse cross-section which is formed on the center of the engaging jig body 41 a in an upwardly projecting manner. The ring member 15 a of the connection member 15 is sandwiched in the engaging portion 41 c.

FIG. 8A to FIG. 8E are explanatory views showing another specific example of the lower irreversible engaging jig 50. Hereinafter, the explanation is made with respect to the specific example of the lower irreversible engaging jig 50 which is constituted of another constitutional element other than the above-mentioned binding band in conjunction with FIG. 8A to FIG. 8E.

In an example shown in FIG. 8A, the lower irreversible engaging jig 50 a is formed by caulking a cylindrical body 50 c made of aluminum. Symbol sod indicates caulked portions.

That is, the lower irreversible engaging jig 50 is mounted in a state that the cylindrical body 50 c allows the connection member 15 to pass therethrough and a center portion of the cylindrical body 50 c is caulked thus sandwiching one of ring members 15 a which are connected with each other while alternately changing the directions thereof by approximately 90 degree by the caulking portion 50 d. Accordingly, unless the lower irreversible engaging jig 50 per se is broken, it is impossible to change a mounting position of the lower irreversible engaging jig 50 from an original mounting position and hence, the float 16 whose downward movement is restricted by the lower irreversible engaging jig 50 also cannot change the mounting position thereof in the downward direction.

Further, in using such a cylindrical body 50 c as the lower irreversible engaging jig 50, instead of caulking the cylindrical body 50 c, an adhesive agent may be filled in the inside of the cylindrical body 50 c thus integrally fixing the cylindrical body 50 c to the connection member 15.

In an example shown in FIG. 8B, the lower irreversible engaging jig 50 is formed by adopting so-called “box wedging” and is configured such that a male portion 50 f on which a fishhook-shaped projection 50 e is formed and a female portion 50 f′ in which a recessed portion 50 g for receiving the projection 50 e is formed forms a pair.

Once the male portion 50 f and the female portion 50 f′ are joined to each other, there is no possibility that the projection 50 e is removed from the recessed portion 50 g, and the lower irreversible engaging jig 50 cannot be removed from the connection member 15 unless the lower irreversible engaging jig 50 is broken. Here, the lower irreversible engaging jig 50 may be configured such that the male portion 50 f and the female portion 50 f′ are forcibly separated from each other and are joined to each other again. However, in such a case, the projection 50 e of the male portion 50 f is deformed and hence, the lower irreversible engaging jig 50 cannot perform the desired function as a jig.

In an example shown in FIG. 8C, the lower irreversible engaging jig 50 is, in a state that the connection member 15 is allowed to pass through the float 16, formed of a sleeve 50 h which is interposed between the float 16 and the discharge valve 13 and has a length equal to the whole distance between the float 16 and the discharge valve 13. Here, the sleeve 50 h may be formed of metal or synthetic resin. Further, also in this case, an adhesive agent may be filled in the inside of the sleeve 50 h thus integrally fixing the sleeve 50 h to the connection member 15.

In examples shown in FIG. 8D and FIG. 8E, one portion of the connection member 15 is used to form the lower irreversible engaging jig 50.

That is, in the example shown in FIG. 5D, one of the ring members 15 a constituting the connection member 15 is formed of a large ring member 15 b having a diameter larger than a diameter of the insertion hole 16 c of the float 16.

Here, in the example shown in FIG. 5D, when the ring member 15 a is formed into a ring shape by making end portions of linear metal materials having plasticity abut each other, for example, the lower irreversible engaging jig 50 which is formed of the large ring member 15 b can be removed from another connected ring member 15 a by plastically deforming (breaking) the lower irreversible engaging jig 50 and by separating the end portions of ring member 15 b which are brought into contact with each other using a tool such as pliers. However, once the lower irreversible engaging jig 50 is removed from the connection member 15 by plastic deformation, even when the lower irreversible engaging jig 50 is deformed with a force so that the end portions are again brought into contact with each other, there is no possibility that the lower irreversible engaging jig 50 reproduces the completely same state as an original state before the lower irreversible engaging jig 50 is removed, and a strength of the lower irreversible engaging jig 50 as a jig is also lowered compared to the strength before the lower irreversible engaging jig 50 is removed.

Further, FIG. 5E is an example when a ball chain is used as the connection member 15. One of ball bodies constituting the ball chain is formed into a large ball body 15 having a diameter larger than the diameter of the through hole 16 c of the float 16.

As has been explained heretofore, according to these embodiments, the mounting position of the float 16 on the connection member 15 is defined by the upper engaging portion 4 and the lower engaging portion 5. Accordingly, when the discharge valve 13 is pulled up by the manipulation of the manipulation lever 14 a, there is no possibility that the float 16 dances and is entangled with the connection member 15. Further, when the discharge valve 13 is opened so that the discharge outlet 12 is released, a quantity of flushing water 3 (5 litters here) defined by the water level FWL at which the tank is filled up with the flushing water and the dead water line DWL of the float 16 is supplied to the toilet bowl 2. Here, the lower engaging portion 5 which defines the movement of the float 16 is formed of the lower irreversible engaging jig 50 and hence, it is impossible to lower the dead water line DWL of the float 16 exceeding the present level thus keeping the supply quantity of flushing water 3 to the toilet bowl 2 always constant. Further, the lower irreversible engaging jig 50 is arranged in a state that the lower irreversible engaging jig 50 is accommodated in the center hole portion 16 a formed in the float 16 and hence, a user or the like cannot get access to the lower irreversible engaging jig 50 from the outside with his/her hand thus making an attempt to increase the supply quantity of flushing water 3 to the toilet bowl 2 exceeding a predetermined quantity more difficult.

Accordingly, for example, assuming a case in which a nation or a municipal authority imposes a legal restriction on the use quantity of flushing water per one use of a flush toilet, with the use of the toilet bowl flushing water tank device 1 of the embodiment, it is possible to prevent in advance an illegal action such as an illegal change of the mounting position of the float 16.

Although the preferred embodiment of the present invention has been explained heretofore, the present invention is not limited to the above-mentioned respective embodiments, and various modifications or variations can be made without departing from the gist of the present invention described in Claims.

Further, the advantageous effects described in the embodiments of the present invention merely enumerate the most preferable advantageous effects obtained by the present invention, and advantageous effects of the present invention are not limited to the advantageous effects described in the embodiments of the present invention. 

1. A toilet bowl flushing water tank device comprising: a flushing water tank for storing flushing water to be supplied to a toilet bowl and forming a discharge outlet which communicates with the toilet bowl in a bottom portion thereof; a discharge valve for opening/closing the discharge outlet; a manipulation portion for performing a pull-up operation of the discharge valve; a connection member for connecting the manipulation portion and the discharge valve, and a float mounted on the connection member in a state that the connection member is allowed to pass through the float and generating buoyancy for maintaining a valve-open state of the discharge valve in a state that the float is immersed in the flushing water, wherein the connection member includes an upper engaging portion and a lower engaging portion for restricting a movable range of the float on the connection member, and at least the lower engaging portion includes a lower irreversible engaging jig having physical irreversibility which prevents the removal of the lower irreversible engaging jig from the connection member unless the lower irreversible engaging jig is broken.
 2. A toilet bowl flushing water tank device according to claim 1, wherein the upper engaging portion includes an upper irreversible engaging jig having physical irreversibility which prevents the removal of the upper engaging portion from the connection member unless broken and/or an upper reversible engaging jig having physical reversibility which allows a change of a movable range of the float due to detachable mounting of the float on the connection member.
 3. A toilet bowl flushing water tank device according to claim 2, wherein the upper engaging portion includes the upper irreversible engaging jig and the upper reversible engaging jig, the upper irreversible engaging jig is arranged in a spaced-apart manner from the float, and the upper reversible engaging jig is mounted between the upper irreversible engaging jig and the float.
 4. A toilet bowl flushing water tank device according to claim 1, wherein the lower engaging portion includes the lower irreversible engaging jig and a lower reversible engaging jig having physical reversibility which allows a change of a movable range of the float due to detachable mounting of the float on the connection member, the lower irreversible engaging jig is arranged in a spaced-apart manner from the float, and the lower reversible engaging jig is mounted between the lower irreversible engaging jig and the float.
 5. A toilet bowl flushing water tank device according to claim 1, wherein a recessed portion which allows the connection member to pass therethrough is formed in a center portion of the float, and the lower irreversible engaging jig and/or the upper irreversible engaging jig is/are accommodated in the recessed portion.
 6. A toilet bowl flushing water tank device according to claim 5, wherein only the lower irreversible engaging jig is arranged in the recessed portion, and the upper reversible engaging jig formed with a diameter larger than a diameter of the lower irreversible engaging jig is mounted in a state that the upper reversible engaging jig is brought into contact with an upper surface of the float. 